Mayor Bloomberg will put the proposed ban in front of New York City's board of health, a body he hand picks, so opposition is unlikely. Photograph: Justin Lane/EPA

Michael Bloomberg, the mayor of New York City, has opened a new front in his personal crusade against obesity by proposing a ban on the sale of large-sized sugary drinks in restaurants, cinemas and other public outlets.

Bloomberg's plan will confirm him in the eyes of libertarians and the hugely powerful food lobby as "Nanny-in-Chief". But health experts hailed it as a necessary next move in the battle to curb the growing obesity epidemic that already grips more than half of adult New Yorkers in its clutches.

Under the proposal, all food outlets currently regulated by the city authorities – including restaurants, street carts, delis, cinemas and sports arenas – would be forced to restrict the size of cups in which they dispense fizzy drinks to a maximum of 16 fluid ounces. That would abolish the large and super-sized containers that are often on sale that can extend to a gut-expanding 64 ounces in fast-food chains.

The restriction would apply to all drinks that contain more than 25 calories per 8 fluid ounces, that is most sodas such as Coke, Pepsi and other fizzy drinks. It would not catch diet sodas or milk-based drinks, allowing the serious coffee addict to continue imbibing giant-sized lattes.

Bloomberg will put the plan in front of the city's board of health – a body that he hand picks, so opposition is unlikely – on 12 June. There will then be a three-month public consultation period, followed by probable imposition in March next year.

In November 2013 any restaurant or other outlet that failed to abide by the new rules would face fines of $200.

"All across the country, everybody recognizes obesity as a growing, serious problem," Bloomberg told the New York Post. "But everybody's just sitting around wringing their hands, not doing anything about it. I think it's fair to say that while everyone else is sitting around complaining, New York City is acting."

Since he assumed office in 2002, Bloomberg has made it his business to try and raise health standards in New York city. He has been at the vanguard of a succession of health drives, many of which have then been copied by states and cities across the US.

Obesity has become a growing preoccupation of the mayor, in proportion to the intensifying scale of the problem. It is estimated that 40% of New York's public school students are obese or overweight, and across America as a whole it is predicted that 42% of the total population will be obese by 2030 if current rates of growth continue.

"The obesity epidemic is a crisis of the first order, and we have been dithering for far too long," said David Katz, a health scientist at Yale and editor of the journal Child Obesity. Among the disasters that have been linked to the epidemic is a dramatic increase in the rate of strokes in children aged five to 14 years.

Evidence is also mounting as to the substantial role that sugary drinks are playing in stoking the epidemic, which city hall blames as the single largest driver of the crisis. It points to the fact that since 1955 the average size of drinks containers at McDonald's have increased by 457%.

The mayor's health advisers also cite a Cornell study that showed that when people were eating soup from a bowl that unbeknownst to them was refilling from the bottom, they took in 73% more than they would from a regular bowl without realising the difference or stopping when they felt full.

Michael Jacobson, head of the health advocacy group Center for Science in the Public Interest, welcomed New York's plans as a move that would be emulated across the US.

"Over the last 10 years it has become clear that soft drinks are a major cause of obesity, and public officials are playing catch-up by introducing policies to reduce consumption," he said.

Early reaction from New Yorkers was mixed. Anna Pirgousis, 23, a diner manager near Union Square in Manhattan, said she thought the 16 ounce upper limit was perfect. "You don't need to drink sizes larger than that."

Pirgousis, a Queens native who has worked in her father's diner since childhood, said she's noticed the city shift toward healthier behavior over the years. "If Bloomberg is really concerned about changing people's lifestyles I think what he's doing is a good thing."

But Jerry Blair, a student at Kingsborough Community College, was unimpressed with the proposed ban. "I think that's ridiculous. Stopping people from eating or drinking something wouldn't mean they'll actively lose weight."

Bloomberg can expect a hurricane-force backlash from fizzy-drink manufacturers and their lobbyists. Already, the New York City Beverage Association has denounced the proposals as an "unhealthy obsession" and a "distraction".

Katz warned that the food industry would prove to be a much more effective adversary than had been the tobacco industry. "Big food is even more powerful than big tobacco, and much harder to resist. Ultimately big tobacco could be turned into the bad guy, but big food sells stuff that is essential for life all mixed up with stuff that causes obesity and diabetes – it's much more complicated."